<?php include 'config/db.php';?>
<!-- 头部header.php -->
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link href="https://cdn.bootcdn.net/ajax/libs/bootstrap/5.3.1/css/bootstrap.min.css" rel="stylesheet">
  <title>课程评价</title>
</head>
<body>
  <nav class="navbar navbar-expand-sm navbar-light bg-light mb-4">
    <div class="container">
      <a class="navbar-brand" href="#">课程评价平台</a>
      <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
      </button>
      <div class="collapse navbar-collapse" id="navbarNav">
        <ul class="navbar-nav ms-auto">
          <li class="nav-item">
            <a class="nav-link" href="/course-evaluation-app/index.php">首页</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/course-evaluation-app/reviews.php">评价</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/course-evaluation-app/about.php">关于</a>
          </li>
        </ul>
      </div>
    </div>
  </nav>

  <main>
    <div class="container d-flex flex-column align-items-center">